The Ideal Weight Calculator estimates a healthy body weight for your height and gender. Enter your height in metric or imperial units and it shows your ideal weight using four well-known medical formulas — Robinson, Miller, Devine, and Hamwi — along with their average and the healthy weight range based on a normal BMI.
There is no single “perfect” weight, which is why the calculator shows several estimates rather than one number. Together they give you a sensible target range. Everything is calculated in your browser and nothing is stored.
How to find your ideal weight
- Choose metric (cm) or imperial (feet and inches) units.
- Select your gender.
- Enter your height.
- Read your average ideal weight, the healthy BMI range, and the result from each formula.
The ideal weight formulas
Each formula starts from a base weight at 5 feet (about 152 cm) of height and adds a fixed amount for every inch above that (or subtracts for every inch below). They differ slightly because they were developed at different times and for different purposes — for example, some were designed for medication dosing rather than general health.
- Robinson (1983) — a widely used modern revision.
- Miller (1983) — tends to give a slightly higher figure.
- Devine (1974) — the classic formula, originally created for drug dosing.
- Hamwi (1964) — one of the earliest, still popular in dietetics.
Which number should I use?
Treat the results as a range rather than a single target. The healthy BMI range (a weight that puts your BMI between 18.5 and 24.9) is the most practical guide for most people, while the formula average gives a useful mid-point. Where you sit within that range depends on your body frame, muscle mass, and overall health.
Frequently Asked Questions
What is my ideal weight for my height?
Enter your height and gender and the calculator shows your ideal weight from four formulas plus the healthy weight range for your height. Because the formulas differ slightly, the best approach is to aim for the healthy range rather than one exact number.
Why do the formulas give different results?
The Robinson, Miller, Devine, and Hamwi formulas were developed in different years and for different purposes, so they use slightly different base weights and per-inch increments. Showing all four gives you a realistic range.
Does ideal weight depend on age or body frame?
These formulas use only height and gender, so they do not account for age, body frame, or muscle mass. A person with a larger frame or more muscle may healthily weigh more than the formula suggests.
Is ideal weight the same as a healthy weight?
Not exactly. “Ideal weight” is a single estimate from a formula, while a healthy weight is a range (based on BMI 18.5–24.9). Any weight within that range is generally considered healthy for your height.
How is the healthy weight range calculated?
It is derived from a normal BMI: the lower end is a BMI of 18.5 and the upper end is 24.9, each multiplied by your height in metres squared.